From a practical standpoint, we know that all material objects are essential for a human beingto build things. This definition includes solids, but also liquid (e. g. , liquid crystals that createLCD displays), and even gases for more specific situations. Really, every raw material used by in-dustry could be included in this classification, but we use the word "material" in a restricted sense :We think about materials whose properties might not be an exact image of those that their elementspossess. Thus, we especially concern ourselves with how elements are structured in macroscopicbodies, with how treatments are used during the elaboration of materials, or with the physicochemi-cal aggregation of different elements——all activities that condition the properties of the materials wegenerate.
The selection, modification, and elaboration of materials to satisfy our needs merge in the foun-dations of human culture. From the very beginnings of prehistory, humans have manipulated sub-stances so that they would be more useful. To create more useful materials, our forebears wanted tounderstand and control the composition of materials, and they often succeeded in modifying a materi-al' s behavior and properties and in predicting the effects of such manipulations.
This task developed over time, beginning as a handcraft that employed empirical and specula-tive knowledge. The history of materials science and engineering had already begun in the Stone Agewhen stones, wood, clay, and leather began to be manipulated. In the Bronze Age, mankind dis-covered the value of temperature and used it to modify materials by thermal treatments or by addingother substances. Yet, in spite of technological improvements, materials science remained empiricaluntil the end of the nineteen century. Materials science, as we now understand it, began with theappearance of Mendeiev s periodic table. Since that time, some properties of elements that are re-lated to their position in the periodic table began to be explained scientifically~, and these resultsbecame incorporated in the annals of science. Since the end of the nineteen century, the introduc-tion of chemistry and physics, calculus, and modem experimentation have brought the use and prof-its of materials to a mature status. Currently, thanks to more reliable knowledge of the structure ofmatter, we can design new materials atom by atom, to achieve the properties we want.
……